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Killer Personalities

Craft vicious villains with this psychiatrist's guide to writing bad guys with real problems.

It's such a disappointment to sit down with a scary novel or crime story, only to find that the killer has been portrayed one-dimensionally. Suddenly, the reader finds himself rolling his eyes in annoyance instead of being struck with fear. Readers want their characters—villains or not—to be realistic and multifaceted. They want to know why a character acts the way he does, and they want it to make sense.

As a psychiatrist and author of thrillers myself, I (like many authors) have turned to specific personality disorders to flesh out a character's motivation behind criminal behavior. Most readers are familiar, for instance, with multiple personality disorder (which tends to translate to one personality being good, while the other is a crazed serial killer). Realistically, though, multiple personality disorder doesn't figure into many real-life crimes and, therefore, it would be implausible in fiction. Not only that, but not all criminals fit this mold. Here's a whirlwind review of the dark side of human nature, so you can craft believable villains and direct your reader into the mind of a madman.


Narcissism is named after the Greek god Narcissus, who fell in love with his own reflection and died pining for a love he could never have. The narcissist is a legend in his own mind; he thinks the world revolves around him. When things go well, he's highly productive and creative. Many politicians, artists, physicians, lawyers and corporate leaders have a healthy dose of narcissism. Narcissists are self-aware; they understand themselves. In moderation, self-love and admiration aren't necessarily bad qualities; they're what give people the confidence needed to take risks.

But a narcissist doesn't take criticism or rejection well. When opposed or slighted, she becomes frustrated, angry, sarcastic, even vengeful. She might steam over an insult and, if the opportunity presents itself, retaliate. If she's highly intelligent, her vengeance could be exacted in an unexpected manner, and no one will ever be able to pin the blame.

When confronted, the narcissist will lie and deny any guilt or wrongdoing, and this is where things can turn ugly—even deadly. Think about politicians who've been confronted with sexual indiscretion: They deny the whole thing, even though everyone knows all will be revealed in the end. Narcissists are natural choices for villains in novels about revenge. One famous example is Sir Arthur Conan Doyle's Professor Moriarty, whose driving motivation was to outwit and destroy his nemesis, Sherlock Holmes.

In my novel The Cadaver's Ball, villain Ed Tyson is a brilliant and highly narcissistic researcher who may well win the Nobel Prize. But the woman he loves rejects him for another man and is killed in a suspicous accident. When she dies, Ed fixates on the man who "stole" her from him and is out for cold-blooded revenge. Unlike the sociopath who feels no remorse, Ed has his own moral code. The wrong that was done to him, and to the woman he loved, must be corrected. If this involves the death of his rival, so be it.

A variant of the narcissist is the malignant narcissist. In addition to the previous qualities, there's an element of sadism—a taking of pleasure from another's pain. The malignant narcissist gets ahead by stomping everyone beneath him. Examples include the bullying sheriff, characters who ruthlessly climb the corporate ladder, and abusive spouses who maintain control through a mixture of oppression and brutality. Part of what makes malignant narcissists get ahead is that while they terrorize their subordinates, they kiss up to their superiors—and they do so in convincing fashion. They're wonderful "yes men" to the boss, whom they secretly despise, because in their hearts they know they could do a far better job.

The antisocial personality

Antisocial personality disorder (aka sociopathy) is a small hop, skip and jump from the malignant narcissist. And this is where we find the mother lode of serious criminal behavior.

From an early age, children who become sociopaths exhibit warning signs. In my second novel, Risk Factor, I used several characters to show how the moral development of such a child becomes warped and distorted. This typically happens through a series of losses, traumas and separations in the child's early life (abuse, divorce, frequent moves, etc.). Just as learning to talk and walk are important developmental milestones, learning to develop empathy also happens at a young age. If this stage is missed or seriously disrupted, a child grows to adulthood with no real concern for the well-being of others; this is the core defect in sociopaths.

Sociopaths believe they're free from the rules of society, and as such, they should be able to have what they want, when they want it, and you'd best not get in their way. Fiction (and real-life prisons) are filled with sociopaths, from Bonnie and Clyde to white-collar criminals who've plundered the retirement plans of their employees. The only time you see repentance from a sociopath is when he's caught, and the remorse isn't for the victims but for himself.

Sociopaths are well suited for a life of crime, as they lack the internal moral workings that lead to feelings of guilt and empathy. Because of this, they stay calm when engaged in high-risk criminal behaviors. Studies looking at heart rate, blood pressure and other physiological indicators of stress have shown that sociopaths aren't easily flustered—a phenomenon referred to as "low arousal." This may also account for how sociopaths can often "trick" polygraph tests.

In Risk Factor, my villain is both sociopathic and narcissistic, a common mixture. What gives him added punch is his intelligence and ability to conceal his inner nastiness. The combination of sociopathy, high IQ and self-awareness is what creates mastermind criminals. These are the most successful sociopaths, as they know how to keep their criminal activities and lack of empathy well hidden. Some sociopaths, like John Wayne Gacy, who tortured, killed and then buried victims in the crawl space of his house, wear the mantel of respectability. This is the killer next door—the one who leaves the neighbors stunned and commenting, "He seemed like such a nice guy."

The borderline personality

Unlike sociopathy, which has a definite male preponderance, borderline personality disorder affects far more women than men. Some speculate that borderline personality disorder is the female equivalent of sociopathy. In this case, instead of acting out in violent ways, the person directs the violence internally. The precipitants of the disorder are similar to what we see in sociopathy but with a high incidence of sexual abuse.

People with borderline personality disorder have chaotic lives that spin out of control in the setting of real—or imagined—rejection and abandonment. Someone with this disorder will overdose or engage in other risky behaviors to try to hold on to people in her life. "If you leave me, I'll kill myself," is a typical strategy for this group, as opposed to the malignant narcissist or sociopath, who might say, "If you leave me, I'll kill you."

The borderline views her world in a black-and-white way. People are either good or bad. Her boss either loves her or is an evil bitch who's out to get her. Borderlines struggle with ambiguity and can't grasp the notion that people are a mixture of qualities. These people are prone to substance abuse, self-mutilation (cutting with razor blades, burning with cigarettes), eating disorders and brief periods of psychosis, where they lose touch with reality. Some people with borderline personality disorder will dissociate, a condition mostly linked to multiple personality disorder (aka dissociative identity disorder).

From a literary perspective, borderlines make fantastic catalysts for action because they're ruled by their emotions; they're not given over to contemplation. They act first and think later, and they have a rare talent for making a bad situation worse. In The Cadaver's Ball, we meet Ann, a beautiful borderline medical student who's just attempted suicide. From there, she seduces, boozes and blackmails her way to an unhappy end.

The paranoid personality

Paranoia is the unrealistic belief that people are out to get you. And because of this, it's not surprising that people with this condition can turn violent: In their minds, they're acting in self-defense.

People with paranoid personality disorder view everything and everyone with suspicion. They can misread a friendly smile as a covert sign that they're about to get fired. An off-hand comment or minor criticism can lead to days of obsessing over the hidden meaning and underlying motivation.

The paranoid, unlike the introspective narcissist, doesn't know he's paranoid. To him, the rest of the world has a problem. He can't understand why people conspire against him, and this makes him angry.

Those with paranoia often lead solitary lives and take jobs where they can be left alone. When a paranoid person turns violent, the anger is most often directed toward the perceived persecutor. People who spin elaborate delusional fantasies about the government are classic examples. A couple of important variants of paranoia include:

• shared paranoia, as seen with some religious and political cults

• drug-induced paranoia, which is common with cocaine and stimulant abuse; it's also standard with cannabis use, although it's less likely to be associated with violent behavior

• paranoid jealousy, where there's a fixed false belief that a beloved is cheating on you. Shakespeare nailed this one when he had Othello smother the virtuous Desdemona.

The truth about personality types—of which there are far more than I've outlined here—is that we all have bits and pieces of different ones. Where a character trait crosses over into something diagnosable, or potentially dangerous, is the terrain that fascinates us. Readers want to know why a 12-year-old shows up to school with murder on his mind, and what made that long-term employee shoot his boss. Understanding these killer personalities gives readers the leg up they need. When such personalities are fully fleshed out in fiction or true-crime writing, we catch a glimpse into the darker side of human nature and are able to understand the mind of the killer living next door.

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